01 -
Whip the soft butter in a bowl until smooth. Toss in sugar and stir just until combined - don't whip it too much. Add flour and mix until you get chunky breadcrumb-like bits.
02 -
Coarsely chop your pistachios. Fold about ⅔ of them into your mixture, saving the rest for the top. Gently work with your hands until nuts are spread through - don't overdo it.
03 -
Pack dough into a cylinder roughly as thick as a paper towel tube. Cover with cling film, press edges closed, and roll it smooth. Stick in fridge for an hour till it's nice and firm.
04 -
Warm your oven to 340°F/170°C. Cut the cold dough into ½-inch thick rounds. Lay them on a baking tray with parchment. Cook for 12-18 minutes till the edges turn slightly golden. Let sit 10 minutes on the tray, then move to a rack.
05 -
Warm chocolate in microwave in short 30-second bursts. Dunk half of each cooled cookie into the melted chocolate, set on parchment, and sprinkle with leftover pistachios. If you want, add a tiny bit of sea salt.